Crane or davit.



A. P. LUNDIN. CRANE 0R DAVIT.

APPLICATION FILED AUG. 23, 1908.

[Patented July 30 A. P. LUNDIN.

CRANE 0R DAVIT.A APPLICATION FILED AUG. 28, 1908.

2 SHEETS-SHEET 2.

w/mfssfl t, l ,j 4roi? f Q @g l.

l er l l Arm/merrnrnn,

@,FICE.

Antennas tnnnin, or naar YORK, n. Y., .assionon BY m'nsnn Assrornvm'nrs,A To

.asron 'rnusr ooiuranr, TRUSTEE, A conronnrron or NEW YoRK. Y

CRANE 0R DAVIT.

Specilcation of Letters Patent.

resented July 30,1912.

.application filed August 28, 1908. ASerial No. 450,605.'

To u!! 'uv/wm. it may conccmf it known that I, ANDREAS P. LUNDIN,

a citizen ot the United Sta-tes, and a resident of the borinlgh of Manhattan, city, county, and State of New York, have'invented certain new and useful :improvements in Cranes or i) v? of which the foliowing is a full,

" o enact description.

, f utilized for either hind or mara tor the handhngot boats or any other toads.

lfn the accompanying drawings, in Which similar reference characters designate corre- -'fe1red formoit my invention, the view 'being partially in cro-sssection; Fig. 2 is an inner or rear View; and Fig. 3 1s a vertical sectlon of the same drivin Referring now'to the preferred form illus-v trated in these drawings, Ar designates a boat provided with a keel a and a Well a.

li 'designates 4the propeller shaft and C bea-ins ruiming longitudinally of the boat and suitably secured to serve as a support for the davitframe.

l) designates the davit or crane frame which may be of any suitable construction. Preferably it will be a casting asshovvn.

iis shown in Figs. l and 3, the frame is provided at its lower portion with a rack E provided with. two sets of teeth e e separated by a raised intermedia-tc rail e2 Which is raised above. the normal level of the casting of the rack proper. This rack may be fast integrally with the frame of the davit or separately therefrom and bolted or otherwise secured thereto.

is shown, the davit arm proper G is provided at its lower end `with a segment G provided with two sets vof teeth g coacting with the teeth .e c of the rack E. Arranged intermediate these teeth g g is a dmvnwardly projecting track g2 shorter than-the teeth g g and adapted to roll along a, torresponding rail e2 of the rackE.

. on relates to improvements in visable in practice to permit of the davit or The davit. arm G is pivotally mounted on t'runnions il and nut K, which nut in turn is mounted on a worm L. The nut K is intei-nelly threaded to correspond with the worm L, which worm is capable of being rotated but incapable of any appreciable longitudinal movement. Obviously, when the worin is rotated in either direction, the traveling nut K will be compelled to move longitudinally carrying with it the dayit' arm G, the segment G of which will then be forced to roll along the rack. The Worm L may be supported in any suitable manner, and I haveI shown it (Figyl) as supported at its inner end in an ordinary bearing in the casting of the frame D and at its outer end supported in an anti-friction bearing in the outer end of the frame D. This antifriction bearing may be of any suitable character, but I have shown it as comprising a series of balis arranged around the outerend ofthe Worm shaft. l

It Will be noticed, Fig. 3, that the frame of the davit arm G is provided with a centrally arranged opening M through Which the Worin passes and in which the traveling go nut and its connection are arranged. As the davit rolls along the rack, assuming that the segment G is quadrant-shaped, there will be some point on the davit arm which will travel in an absolutely horizontal plane. In'practice, l' have found it preferable as a. general proposition to have the segment G approximately a quadrant and t'o pivot the davitto the taveling nut approximately at the aforesaid point. Under certain conditions, however, it ,is advisable to use a segment. having acurve differ-ing somewhatfrom an absolute quadrant. Fiuthermore, it is notl always practicable to arrange the pivot at precisely this theoretical point. Again, thereA is always a possibility of a vrope or some other obstruction ad cidentally getting in the path of the moving quadrant. Again, in the manufacture of davits-\vith segmental lower portions, l

4have found that there is frequently a' variation owing to a greater or less degree of contraction of the Inet-il iii-casting. For these and other reasons, l have found-it adcrane having a certain amount of vertical play with regard to the travelingnut and worin. For this reason, instead of connect yto ing the trunnions directly to the davit trarne, I have shown the trunnions H H extending' into blocks 'N,`whicl`1 blocks may be .of "any desired shape, but. Aare `shown as rectangular, arranged in similarly 'shped'f apertures Itv in the frame. rIhese apertures Parent substantially the s'ame width as to lbe that in which the crane ordavit arm4 proper fis-substantially vertical, in the preerred forni-,of my invention the s ent ae will be arranged to project' at one side of that vertical-.position and atthat side in.

which thefdavit army moves from its normal `positlontojits extreme opposite position. In

such acon'struction, it' will be extremely diliicult to select any point which will trave] in a substantially' horizontal plane. Consequently, the use of the vertically movable blocks N N is 4especially important in such an arrangement. `On the other hand, any construction lvvhich will ermit'lof davit so constructed being moved ackward and torward or caused to roll its segmental lower portion would come within my invention.

In operating adavit or crane of this con`` struction, Inlay use either one single davit or two working together.v For example, on;

a long heavy boat, I should prefer to use two, one connected with` each end thereof. Similarly, on a very W'de boat, such asa lighter, or any other wide object, I might use four or more cranes 0r davits 'as for example, two at each end and at either sidethereof. For ordinary work, one will suffice. Where one alone is, used, and even insome cases'where moreiare used, there lwill be considerable side strain on the davit.v This will be counteracted, to a certain extent, by theupwardly projecting ,anges e3 e3 on the f rack arrangedto project upward and out- .davit arm. Furthermore, (Fig. 3) I'prefer vto secure a lateral guide-plate in the frame f- .D. This plate will preferably be made of 4'-bronze'andv be located as indicated by R in thel space above the traveling nut. It may b'e 'se'cur'ed in any suitable manner, but I haveLf-shown it (Figs. 1 yand 3) as being ,bolted or riveted byl bo-lts or rivets 'r to the underside of a T-plate T, which rests upon andissecured to'each end of the frame or casting D. This construction not only provides'. al guide to take-np lateral strains as the davit moves backward and forward, but also materially strengthens and st'iii'ens the'. frame and entire structure. Furthermore,

same time suiiiciently closeito the top gagement therewith in the event of an obextreme outer position or between that and side of the teeth g gof the segment of the it should be arranged sufiiciently far above the traveling nut to permit of the vertical lay or movement already described as being permitted by the blocks N N, and, at

off-the xtraveling nut to,prevent. the same from rising a suiiicient distance to permit the segmental lower end of the davit to leave the rack or to be forced out of enstacle being met. Of course, the guide-plate R will be of such width compared with the area of the aperture in the davit arm -at that point merely to leave enough clearance on eithel` 'side thereof to permit of an easy longitudinal movement,-so as to retain the davit arm in a substantially constant upy,right position both as against any side strains resulting from' -a load and also Iagainst any tendency to tilt due to the frolling of the vessel or other causes.

-S designates -an'a'dditional brace arranged 'at the outer end Yof the frame to take care ot outward strains lwhen'the davit is in its a substantially vertical position.

In an earlier applicatiom- Serial No. 404,829, filed December 2, 1907, I have .shown a hoisting .apparatus working in combination with this general type of davit or'crane. Consequently, I `do not broadly claim herein the combination of a drum with this general type of davit. I have found, however, that 4in certain class ofwoik, and particularly on comparatively -small launches or wherever the operating space is small, that it is important to have ,the operating mechanism as close togetherias possible. For example, in the type of boat illustratedl in the accompanying draw' ings, practically the only place from which the apparatus could be operated conveniently would be in the well a. Under such or similar conditions, it b comes important to have both the davit an the hoisting apparatus` operated from substantially the same point. 4 Y

As shown in the drawings, the inner end of the. worm shaft is cut square to permit4 the attachment thereto of a liandle V for turning the same. 4 Arranged in a portion of the cast-ing near thereto is shown another attachment W for the handle V to drive a wheel X keyed to a shaft Y which passesthrough an aperture y in uthe casting of the trame Deand has keyed to its other end a hoisting 'drum Z. Amrope l has one end seured tothi/sfhoist-ing drum and passes over a pulley ".2 arrangedin the upper or outer end of the davit arm G and from there outboard, being provided at its outer end with a suitable securing device for the object to be handled.

3- designates a pivot, such as a stout hinge provided at one side of the davit casing 130 and t securinganeans, such as a series ot' bolts and nuts arranged on the opposite side ot' the casting or trame. I By removing these nuts. the entire davlt may be swung sidewise on the hinge 3 and the davit or the way on a small boat applies equally welli to any other conditions where the same eircmnstances exist or where'the same results are desired, such. tor example, as on fiat Cars, carts, crowded docks, yards, etc.

The operationot' the preferred form o my apparatus is as follows: If it is desired to pick up a given object from a given spot.l and move ity to another point, it may or may not be necessary to make any use of the hoisting drum. The

position shown in Fig. l, three separate movements take placesimultaneously. In

vthe first. place, the rope being secured to vlower away into thel water or a nearby vessel. On the other hand, ,under some circumstances, the 'hoisting apparatus will be utilized first to raise the load to a certain point and then the. davit operated to raise it still farther and clair. In other words, the hoisting apparatus in some cases continues the initial 'upward or downward movement ot' the load which has been started by the mere movement of lthe davit, and -in other cases, the movement ot' the davit continues and completes the upward or downward movement of the load commenced by the hoisting apparatus. Furthermore,by using two handles and slacking away on the hoisting di im while operating the davit worm, the strain on the latter may be considerably diminished. In

other words, a davit of this type', as it is operated from either extreme position toward the center, raises the load. It' a hoist ing drum is rotated in an oppositedirection at a suiicient speed to slack away'to the same extent asthe davit is taking up, or in other words. to keept-he loa-d in a substantially horizontal plane, all strain on the d-avit due to its take up, Will'be doney Similarly, if the load is to be4 lowered to a point below its initial posit-ion,

a way with.

moment the davit-` worm is actuated to roll the davit from the by .lowering at the same time the davit is swinging in either direction` the ease ot' operating the davit will be considerably increased for the same reason.

'I t. will be noticed further that b v the use ot' my invention` the center ot' gravity of the entii'e construction will be a `point considerably lower than that in other devices.

I do not mean to draw any distinct-ion in thisI application between a da vit and a rrane,'

as by the wordfdavit" I mean .nothing more than a small crane, more particularly adapted t'or use on ships.

What I claim asnew is:

1. A crane having a lower portion provided with a segment having two sets ot' teeth arranged on either side of a track.` in combination with a rack rovided with an intermediate rail upon which the track rolls and two sets' of teeth on each side ot' said rail adapted 'to engage and co-aet with the teeth on the segment.-

A frame secured to a support, a worm rotatively mounted in Asaid frame, a crane arm provided with an opening substantially '.nect-ing said blocks'and said traveling nut.

4., The combination f a crane arm, a forwardly-extending segment at its lower end, a support upon which said seglnent may roll, a movable pivot traveling substantially parallel to said support andabout which Said crane may turn, means for permitting vertical play between said pivot and crane, and means for moving said pivot.

' 5. The combination of a crane, a movable pivot on which said arm may turn, a fon' wardly-extending toothed segment at the lower end of said arm, a rack on which said segment. may roll, means for moving said pivot substantially parallel to said rack,

and means for permitting vertical play between the crane and pivot.-

6. The combination ywith a :crane arm adapted to swing and provided with an aperture extending in the direction of its swinging movement., of, a. lateral guide and strain pate fixed to a support-.and adapted to engagewith' the side wallsof said aperture.

7 The 'combination with a crane arm, ot aV pivot on whichgit isl adapted to swing the said pivot being vertically-,movable with up side strains therefrom, .and to limit the extent of vertical movement of the regard to the crane arm, and a guide plete name to the foregoing speoiCa-ton in the constructed -and arranged at once -to serve presence of two subscribing Witnesses.

as a lateral 'guide for theerane armo, to ,take ANDREAS P LUNDIN W tnessee:

L. D. JAKINS, o

JOHN C. SILVA.

aforesaid pivot. r ,Y

AIn Witness whereof, I have signed Copies of this patent may be obtained for fivel eents ech,`by addressing the Commissioner of Patents.

' Washington. 1).0. 

